Drill-spindle.



No. 795,123. PATBNTED JULY 18, 1905.

' R. G. HENRY n D. M. WRIGHT.

DRILL SPINDLE. APPLIoATIoN FILED MAB. e, 1905.

@www f Patented July 18, 1905.

PATENT Orrin ROBERT Cr. HENRY AND DANIEL M. WRIGHT, OF HARTFORD, CONNECTICUT.

DRILL-SPINDLE.

SPECIFICATION forming' part of Letters Patent No. 795,123, dated July 18, 1905.

Application filed March 6, 1905. Serial No. 248,538.

T0 (1J/Z whom, t may concern,.-

Be it known that we, ROBERT G. H nNRY and DANIEL M. WRIGHT, citizens of the United States, residing at Hartford, in the county of Hartford and State of Connecticut, have invented a new and useful Drill-Spindle, of which the following is a specification.

This invention relates to the construction of a drill-spindle for a sensitive drill-press.

The object of the invention is to produce a spindle which can be manufactured at much less cost and yet will have a stronger drive and be more durable and satisfactory than prior spindles for this type of machine. A

All spindles for machines of this class are provided with an adjustable collar to prevent the spindle from jumping and the drill becoming damaged when breaking through a hole. It has been thc universal custom in constructing spindles of this character to turn a thread on thc spindle near the middle of its length and adjacent to the upper end of the racksleeve and screw an adjusting-collar on this thread. In order to provide for this thread and allow the adjusting-collar to be located on the thread, it has been necessary to turn down the upper or driving portion of the spindle. Turning down an extended portion of the upper end and threading a long spindle near the middle is an expensive operation, owingl to the labor required to accurately adjust the spindle in the fixtures, the time consumed in cutting away the metal, the stock wasted, and the wear of thc'tools. The greatest objection, however, to this is that the upper end being' reduced with relation to the lower end of standard size requires the driving partuthat is, the part which connects the driving-pulley witlrthe spindle--to be much nearer the axis of the spindle than if the spindle were not turned down.v

This not only weakens the spindle, but makes the driving connection between the pulley and the spindle weaker. A spindle constructed according to this invention is of equal diameter throughout its entire length, thereby greatly reducing the cost of construction and providing a stronger spindle and a firmer and more durable drive.

Figure 1 of the accompanying drawings shows a side elevation of a sensitive drill-spindle that embodies the invention with portions cut in central section in order to illustrate the construction.

same.

The spindle 1 is preferably a bar of steel of uniform diameter throughout its length. The lower end of the spindle is provided with an opening for receiving the shank of a drill or a chuck, as the case may be. Fixed to the spindle, preferably by sweating, is a thrustcollar 2. Above the thrust-collar are ballplates 3 and 4, with a ball-holder 5, containing balls 6, between the plates. Above this ball thrust-bearing is the sleeve 7, which is provided With a rack that is adapted to mesh with the feed-pinion. A collar 8 is fixed to the spindle above the rack-sleeve preferably by means of a pin 9, that is driven from one side of the collar to the other through the spindle. On the lower end of this collar is a hub 10, which is provided with an exterior thread, and turning on this threaded hub is an interiorlythreaded ring 11. The threaded ring is fixed in position by a set-screw 12. Between this ring and the upper end of the rack-sleeve is a washer 13, which is preferably formed of hard liber.

The form of spindle shown is provided with longitudinal grooves 14 in its periphery at the upper end, and the d riving-pulley 15 has rolls 16, which extend into these grooves. These rolls permit the spindle to move freely up and down through the pulley; but they act as keys and require the spindle to rotate with the pulley.

The adjustment to prevent the drop of the spindle when a hole is broken through is attained by turning the ring on the threaded hub of the collar that is pinned to the spindle above the washer at the upper end of the rack-sleeve. It is a simple matter to form and thread this collar and [ix it to the shaft, and the ring is easy to make and apply to the collar. The adjustment can be obtained in a satisfactory manner without exposing the threads. The threads being concealed do not catch dirt and chips and become worn.

With this construction it is unnecessary to Fig. 2 showsa planA of they turn down the upper portion of the spindle, and on account of this the driving-grooves can be some distance from the axis of the spindle, which results in a strong spindle and a poiverful drive. This spindle, which is Vof equal diameter throughout its length, can be ground at one operation, and consequently a fine fit lproduced with but little expense.

The invention claimed is y l. A drill-spindle for a sensitive drill-press of' uniform diameter throughout its yentire length and having a threaded collar fixed upon it, and a threaded adjusting-ring turning on the collar, substantially as specified.

2. A drill-spindle for a sensitive drill-press of' uniform diameter throughout its length and having a collar fixed upon it, said collar hav- ROBERT G. HENRY. DANIEL M. WRIGHT..

Witnesses:

HARRY R. WILLIAMS, ETHEL M. LOWE. 

